Pump



Nov. 4, 1930. c'qM. BoLsTER PUMP V 4 Sheets-Sheet 2 @noa/Moz Filed Dec.- 23, 1927 .w wmv @HAAT 1.511% @l f EN l lp @www f www Q f /V/ QN vh V Nw M ANOV. 4, 1930. C, M. BOLSTER l 1,780,614

4 Sheets-Sheet 5 Filed De CALVIN MEQLSTEEOE LAKEHURsT, NEW V'JERSEY f ','Appu-caton ined December 23, 1927. seriiNm 242,079.

This invention vrelates to rotary pumps,-

, compressors or similar devices, and has for` one of its objects the provision of'an improved device of this character which will be relatively .inexpensive :to manufacture, 'and highly efficient inV its operation 1 VFurther fobjectsfand various features of novelty Will be apparent from the following description and accompanying illustration of a specific embodiment vvhichfor .Couveny ience-and simplicity will be referred to as a pump. ln the drawings:

F ig. 1 isanend elevation of the pump taken from the left of ,Fig..2; l'

right of Fig.'1;V Fig. 3 is an-end tially on the line removed;y l l v Fig. 4 is a central vertical longitudinal section takenk on the line 4440i Figs. 1

elevation taken substan- Fig.| 5 is an end elevation takenfsubstaning head and rotor yend plateremoved;

`Fig.r 6 is a'central vertical transverse section taken on line G-Gfof Figs. 2 and 4; and Figs...7 to 10 are diagrammatic vieWs taken at different periods in the operation. By reference to the drawingsit Will bevob-lil served thatthev apparatus comprises arcas ingA including an intermediate-or body per# tion 12i and spaced heads 13 and l14v securedV to the ends of, the intermediate sectionby screws 15 or equivalent devices.4 .The intermediate vportion Of the casing is provided'y Witha cylindrical pressure chamber 1 6 into Which open an inlet passage 17 and an outlet ypassage' 18, each of which passagesv termi* nate's in a narrovv' slit-like longitudinal portV 19 at'k its inner end and is provided with a coupling nipple 20 at its outer end for attachment ofsuitable pipes for conducting fluid into and out of the'pressure chamber of the 5 pump.` EachV of thefheadsxland 14Vis'pro- 7 vided with shaft bearings 22 axially concentric With the cylindrical pressure chamberfor the reception of a rotor shaft. The bearing bore for the head 14 extends entirely through 5 0 the head, including an annular projection Fig. 2vis a side elevation taken Vfrom the S--Sfof 4 withy the head tially' on .theline 5 5 of Fig. 4 with the caspressure chamber 1G; and aneccentric por- The. proj ection is counterbored from itsouter end to furnish an annular' packing space and is externallydireaded to' receive a packing retaining nut 24. f' fA According to this kinvention means islpro vided Within thecylindrical pressure chamber to form With the Walls thereof, a Working space Yfor handling the fluid and alsofor forcing the iiuid between the inlet andoutlet. Various forms of devicesmay be employed for Athis purpose but theforrn which' is pre-Y ferred and f which willV be particularly de .scribed by' Way of example herein consists of a rotor B includingashaft 30, anda piston'k 31 preferably vformed integral with the shaft.A

The shaft ends operate within thebearings l 22 provided therefor-in theheadsl 4and14 and vone end `ofthe shaft `extends vthrough the head 14 for attachment of a pulley, gear o r any yequivalent driving member; The piston 31 is formed With a concentric pcrtion-32 struck from the chamber and shaft centerv a,

adapted to'have a kclose Working contact with the interior peripheral Wallvof the cylindrical imizing leakageof iuid therealong .and to contact surface-to the cylinder Walls forininy cover both` the inlet'and outlet portsWhen.y

passing the saine foray purpose hereinafter disclosed; As shown it subtends an angle of approximately ninety degrees. Means is provided for closing the ends of the Y cylindrical pressure chamber 16 about kthepiston 31. This means maybe provided either asapart of the casing or as .apart of'v` .the rotor depending upon thestructural dispcsitionof certain relatedparts Will be obvious vvfrom the entire des'cription Herein 1t comprises "spacedend plates 36 having an interior opening fitting closely about .hubs'187 provided on the rotor and secured to theends According to this invention ineansis'provided to cooperate with the piston to furnish preferably operated positively from the mov- Vee ing rotor and desirably also is arranged to have a close workingfit with a portion of the piston 31. This means may comprise an abutment 40 slidably mounted in an oscillatory cylindrical block 41 i tting tightly within a 'cylindrical bore 42 provided in the casing.

A channel 43 is formed in the casing between the chamber 42 and the pressure chamber 16 to accommodate the, abutment inits oscilla-v tory movement.

The abutment may be operated from the '.otor in 'various ways.V The construction herein shown comprises an eccentric groove 45 formed in each of the rotor end plates 36, which grooves are struck from the center Eccentric straps 46 fit into these grooves 45 ind are formed integral with extension piecesl 47 secured to each end of the abutment 40 by screws 48 or the like, the extension 47 being of the same'width as the abutment and also fitting within the cylindrical oscillating f blocks 41.

Provision is herein made for closing the ends of the connecting` channel in which the abutment operates. This is accomplished'in part by the outer edges ofthe rotor end plates 36 but, in addition thereto, packing plates 50 are employed. rFliese packing plates 50 have an arc-shaped surface 51 of the same curvature as and closely engaging the oute' periphery lof the end plates.` They may be secured by screws 52 or the like to the casing at either side of the oscillating vblock 41 as is most clearly seen in Fig'. 3.

position as well as to prevent leakage past the ends of the same.

The inner face of the abutment 40 is formed on an arc struck from the 'eccentric center the radius of the arc being the same as the radiusof the eccentric portionv 33 of the piston. From this it will be seen that the abutment will closely engage the Veccentric portion of the piston at all times during its passage but will stand above the concentric portion 32 of the piston while the same is passing the abutment7 thus avoiding wear on the latter. Since the virtual center of connection of the abutment corresponds with the center of the eccentric portion of the piston it will be obvious thatt-he arc face of the abutment will fit upon thisY eccentric portion throughout its length in all rotatedpositions ofthe piston and corresponding oscillated positions of the abutment.

This invention also contemplates the employment of suitable packing upon the abutment and upon the interior surface of the cylindrical pressure chamber for minimizing leakage in the operation of the piston. The packing on the abutment may consist of several longitudinal packing strips 55 set into The plates 50 also serve to retain the block 41 in correct ing into the pressure chamber when not engaged by the concentric portion 32 of the piston.

Preferably means is provided on the rotor for removing grit or other solid material from the chamber and this may: be accom-Y plished by a small longitudinal groove 35 provided on the piston.

The operation of the pump may be understood by reference to the diagrammatic Figres 2' to 10. In Fig. 7 the trailing end of the concentric portion of the piston is just passing the edge of the slit-like inlet port 17 While the working space filled with fluid is disposed on the opposite side of the cylindrical chamber and fluid is being forced from the outlet port 18. Inthis view the abutment 40 has been drawn into close engagement' with the eccentric surface 33 of the piston. Fig. 8 shows the parts at approximately mid stroke where the abutment forms a tight closure between the inlet portY and the outlet port. Fluid is being drawn in at the inlet and discharged at the outlet.v Fig. 9 shows the position of parts at the completion of the working stroke. Here the working space 34 is positioned adjacent thel inlet port and the piston has completed expulsion of fluid bevtween itself and the abutment-through the outlet port. The abutment has not quite begun rising out of contact with the piston.

In Fig. 10 the parts are shown during the transition period while the concentric portion of the piston is moving between the out-v let and the inlet. The abutment is vraised above the surface of the piston but the concentric surface of the piston is of sufhcient length, as has alreadybeen explained, to close both inlet and outlet ports to prevent the flow of fluid therebetween. This closure is effected from the time the forward edge ofl the concentric portion of the piston engages the edge 6() adjacent the outlet port until the trailingV edge of the concentric portion 32y i What I claim ist or the like, in combi- 1. In a rotary .pump

l nation, a casing comprising an intermediate portion having a cylindrical chamber and circumferentially spaced inlet and outlet ports, and heads at either end 4having shaft bearings coaxial With the chamber, a rotor comprising a shaft journaled in said' bearings, a piston fast on said shaftvvithin said chamber having a portion concentric With the chamber and an eccentric portion defining with the Walls of said chamber a Working space, and cir-cular end plates secured to the piston closing the ends. of said chamber, said end plates having grooves onv their inner faces concentric With the eccentric portion of said piston, an abutment disposed between the inlety and outlet ports comprising a blade adapted to cooperate vvithl said piston and end portionsfitting in said rotor plate grooves for imparting movement to said abutment, an oscillatoryl block slidably receiving said abutment, packf ing plates fixed to said casing bearing along an arc at one edge thereof upon the circumference of said rotor plates and on a face thereof against the ends of said abutment and oscillating block for preventing leakage,

longitudinal packing strips on said abutment blade'adapted to bear upon the eccentricporin correct position.

In a rotary pump or the like in combination, a casing 'comprising' an intermediate portion having a cylindrical chamber yand circuml'ierentially spaced inlet and outlet ports,'and heads at either end, a piston rotatable in said chamber, said piston having a portion in contact With the chamber Walls and a portion eccentric with respect to the f chamber and the axis of rotation of the piston, an oscillatable and slidable abutment adapted to operate in engagement With the eccentric portionof said piston, and means operatively connecting said abutment with said piston, said means having an yeffective centerof connection With said abutment coinciding With the center yof the eccentric'portion of said piston.

3. In a rotary pump orthe likeincembination, a casing havinga cylindrical chamber and spaced inlet and outlet-ports opening Y into the chamber, a rotatable piston operable in said chamber having aportion concentric With and, substantially incontac't with the peripheral Wall of the chamber and an eccentricportion, an abutmentv associated with tion, ,a casinghaving. a

` cut away to ypermit` oscillation Vber having an annular ring `groove fand a portion secured to the end of saidpistomandmeans to 'causey said labutment toengage said'eccentric piston portion throughout yits length but to stand clear of said concentric portion. While thesameis passing the abutment, said concentric portion at such times providing a separation between the inletand outletfportson the sideon which theabutment is located. f l 4. In a rotary puinp or the like in combinacylindrical chamber, a rotor comprising a piston rotatable in said chamber, end members `closing the ends of Vsaid chamber vabout the piston, an oscillatingv and" reciprocating abutment adaptedfto cooperate With said piston, said casing being `ofthe abutment, eccentric-'means for operating saidV abutment from said rotor, andA means cooperating Withthe end members of said rotor to vseal the endsl ofthe cut avvay portion of the casing. 1 i

6. In a rotary pump orthe like in combination, a rotatable piston, an oscillatory and reciprocatory abutment cooperating With said piston, vice for operating `aid abutment in timed relation with said piston. 7 In a rotary pump or the like in combination, a rotatable piston having a portion concentric-With the aXis of rotation and a circular portion eccentric to the axis of rotation, an oscillatable and reciprocatable abutment cooperating with said piston, and means 'including' an eccentric device for operating said abutment by movement derived yfrom 5.'v In a rotary pump or the like in combina- ,i

and means including an eccentric desaid piston, said means including a rotatable member having a virtual connecting center With said abutmentvvhich coincides With the center of the eccentric portion of said piston.

8. A devicejas set forth in claim 6in which said connecting means further includes an eccentric strap secured to the end of said abutment.

9. A device as set forth in claim 6 in which said keccentric device comprises a grooved plate secured to the end of said piston.

l0. A. device as set forth in claim 6 in Which said eccentric device includes a grooved plate secured to the end of said piston anda memfitting in said said abutment.

11. In a rotary pump, a casing having a cylindrical chamber, al flanged rotor disposed in said chamber, andv packing strips disposed Within the peripheral Wall of the chamber and retained in position by engagement with the rotor Hanges.

12. In a rotary pump, a pair of spaced rotatable plates having grooves therein, a slidable abutment provided with end eXtensions disposed Within said grooves,y and said slidable abutment having a concave bearing surface, and longitudinal strips set into the abutment to tace with said concave surface and provided with portions extending into the grooves of the plates to retain said packing strips in correct position.

13. Apparatus of the character described comprising a' casing having ya cylindrical chamber, a rotatable piston disposed in said chamber and having a longitudinal notch on its periphery for removing grit from the surface of said cylindrical chamber With which said piston is adapted to cooperate.

14. Apparatus of the character 'described comprising a rotary piston having a concentric portion and an eccentric portion, a slidable abutment and means to raise said abutment clear of the concentric piston portion b ut allowing it to vengage the eccentric por-y tion.

In testimony whereof, I have signed .my name to this speciiication this 19th day of December, 1927.

CALVIN M. BOLSTER. 

